ferrous oxide

American  

noun

Chemistry.

1. a black powder, FeO, insoluble in water, soluble in acid.

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ferrous oxide Scientific  

1. A black powder used to make steel, green heat-absorbing glass, and enamels. Chemical formula: FeO.

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Etymology

Origin of ferrous oxide

First recorded in 1870–75

Example Sentences

Amused and enchanted, I named him "Ferrous" for the chemical name of rust, hydrated ferrous oxide.

From New York Times • Feb. 13, 2018

When oxygen, in a free or gaseous state, comes into contact with iron, it produces ferrous oxide, which is recognized as rust.

From Electricity for Boys by Zerbe, James Slough

Ferrous Oxide.—When a qualitative test shows both ferric and ferrous oxide to be present, the proportion of the ferrous oxide must be separately determined.

From A Text-book of Assaying: For the Use of Those Connected with Mines. by Beringer, Cornelius

Organic acids, ferrous oxide, chromic oxide, ammonium salts, etc., prevent the formation of peroxide and the red color produced by permanganic acid.

From Scientific American Supplement, No. 441, June 14, 1884. by Various

For example, ferrous oxide is FeO and ferrous chloride is FeCl2, and, again, ferric oxide is Fe2O3, whilst ferric chloride is Fe2Cl6.

From A Text-book of Assaying: For the Use of Those Connected with Mines. by Beringer, Cornelius